Support unlimited number of host names in a single line of the known_hosts file.
Support unlimited number of host names in a single line of the known_hosts file.

Previously the code assumed either a single host name or a hostname,ip-address pair.  However, according to the spec [1], there can be any number of comma separated host names or IP addresses.

[1] http://www.openbsd.org/cgi-bin/man.cgi?query=sshd&sektion=8

libssh2/libssh2,libssh2/libssh2,libssh2/libssh2,libssh2/libssh2